checked in new files

eng/common/scripts/Helpers/Metadata-Helper.ps1

@@ -0,0 +1,58 @@
+function Generate-AadToken ($TenantId, $ClientId, $ClientSecret) 
+{
+    $LoginAPIBaseURI = "https://login.microsoftonline.com/$TenantId/oauth2/token"
+
+    $headers = @{
+        "content-type" = "application/x-www-form-urlencoded"
+    }
+
+    $body = @{
+        "grant_type" = "client_credentials"
+        "client_id" = $ClientId
+        "client_secret" = $ClientSecret
+        "resource" = "api://repos.opensource.microsoft.com/audience/7e04aa67"
+    }
+    Write-Host "Generating aad token..."
+    $resp = Invoke-RestMethod $LoginAPIBaseURI -Method 'POST' -Headers $headers -Body $body
+    return $resp.access_token
+} 
+function GetMsAliasFromGithub ($TenantId, $ClientId, $ClientSecret, $GithubUser) 
+{
+    $OpensourceAPIBaseURI = "https://repos.opensource.microsoft.com/api/people/links/github/$GithubUser"
+
+    $Headers = @{
+        "Content-Type" = "application/json"
+        "api-version" = "2019-10-01"
+    }
+
+    try {
+        $opsAuthToken = Generate-AadToken -TenantId $TenantId -ClientId $ClientId -ClientSecret $ClientSecret
+        $Headers["Authorization"] = "Bearer $opsAuthToken"
+        Write-Host "Fetching aad identity for github user: $GithubUser"
+        $resp = Invoke-RestMethod $OpensourceAPIBaseURI -Method 'GET' -Headers $Headers
+    }
+    catch { 
+        Write-Error $_
+        return $null
+    }
+
+    $resp | Write-Verbose
+
+    if ($resp.aad) {
+        Write-Host "Fetched aad identity $($resp.aad.alias) for github user $GithubUser."
+        return $resp.aad.alias
+    }
+    Write-Error "Failed to retrieve the aad identity from given github user: $GithubName"
+    return $null
+}
+
+function GetPrimaryCodeOwner ($TargetDirectory) 
+{
+    $codeOwnerArray = ."$PSScriptRoot/../get-codeowners.ps1" -TargetDirectory $TargetDirectory
+    if ($codeOwnerArray) {
+        Write-Host "Code Owners are $codeOwnerArray."
+        return $codeOwnerArray[0]
+    }
+    Write-Error "No code owner found in $TargetDirectory."
+    return $null
+}